1. Field of Invention
The present invention relates to sportsballs, and more particularly to a durable sportsball adapted for mass production, wherein the sportsball can retain its spherical shape and distribute an impacting stress throughout the ball.
2. Description of Related Arts
Sportsball such as soccer ball and volleyball generally comprises a ball cover and a bladder disposed inside the ball cover. The ball cover, which is preferably made of leather or synthetic leather, has a valve hole provided thereon and consists of a plurality of panels connected edge to edge by machine sewing to form a roundness shape wherein the ball cover is composed of an outer coating, an intermediate layer, and an inner lining layer to strengthen and support the intermediate layer.
Accordingly, the sportsball further comprises an exterior web layer integrally adhered on an outer surface of the bladder wherein the web layer has at least an elongating strengthened thread evenly wound around and around the outer surface of the bladder. So, the strengthened thread is overlapped with each other to form the web layer to entirely embrace the bladder for supporting the ball cover and resisting the stress and impact force of the sportsball.
Since the panels are edge to edge connected together, the ball cover cannot be formed as a prefect spherical interior such that when the bladder is received in the ball cover, the inflated bladder will not fit into the ball cover in full contact, especially at the edges of the panels of the ball cover. Thus, the edges of the ball cover will affect the roundness of the sportsball.
Furthermore, the leather or the thickness and hardened synthetic leather ball cover may make the players feels hurt and pain while contacting the sportsball, especially to children and those training players.
A main object of the present invention is to provide a sportsball which comprises a ball cover well supported by a strengthened bladder. Therefore, no additional lining is required to adhere onto the ball cover, so as to lower the material and manufacturing cost of the sportsball.
Another object of the present invention is to provide a sportsball which has a stress absorbing layer to reduce the painful during contact, especially suitable for children and training players.
Another object of the present invention is to provide a sportsball wherein the bladder has a better flexibility and impact resisting ability.
Another object of the present invention is to provide a sportsball wherein the stress absorbing is adapted for fittedly filling a gap between the ball cover and the bladder so as to provide a better roundness of the sportsball.
Another object of the present invention is provide a sportsball wherein since the stress is distributed on the stress absorbing layer and the bladder but not the ball cover, the expensive leather panels of the ball cover can be thinner to lessen the cost.
Another object of the present invention is to provide a manufacturing method of a sportsball which enables the ball cover to be sewn by sewing machine, and thus it is suitable for mass production.
Accordingly, in order to accomplish the above objects, the present invention provides a sportsball, comprising:
a ball cover having a valve hole provided thereon and a plurality of panels connected edge to edge to form a roundness shape, wherein each of the panels having a predetermined shape has an outer coating layer, an inner lining layer, and an intermediate layer which is integrally formed between the outer coating layer and the inner lining layer and is strengthened and supported by the inner lining layer;
a bladder which is disposed inside the ball cover comprising a bladder ball, an exterior web layer integrally attached on a predetermined area of an outer surface of the bladder ball, and a valve stem which is mounted on the bladder ball and is outwardly extended to an exterior of the ball cover through the valve hole for air inflation, wherein the web layer comprises at least an elongated strengthened thread evenly wound around the outer surface of the bladder ball in such a manner that the strengthened thread is overlapped to form the web layer to entirely embrace the bladder ball for supporting the ball and resisting the stress and impact force applied to the sportsball; and
a stress absorbing layer comprising a plurality of absorbing pad having a flexibility ability fittedly attached to the panels respectively for filling up a gap between the ball cover and the bladder, so as to increase the contact area therebetween and reinforce the roundness shape of the sportsball.
Thus, the present invention also provides a specific manufacturing method for producing the sportsball, which comprises the steps of:
(1). Inflate a bladder ball which has a valve stem provided thereon.
(2). Coat at least an elongated strengthened thread such as nylon threads with glue.
(3). Wind the strengthened thread evenly around an outer surface of the bladder ball until the bladder ball is embraced by a web layer of the strengthened thread to form a strengthened bladder.
(4). Heat the bladder in a mold until the web layer is permanently and rigidly united with the outer surface of the bladder ball.
(5). Cut a ball cover material, such as leather or synthetic leather made of foaming PU or PVC sponge material, into a predetermined number of panels in predetermined shape. For soccer ball, 12 pieces of pentagonal panels and 20 pieces of hexagonal panels are cut. For volleyball, 18 pieces of panels in two kinds of rectangular shape are cut.
(6). Sew the panels edge to edge together by sewing machine to form a ball cover which has a valve hole provided thereon, wherein a section of panels is remained unsewn to form an inlet opening.
(7). Cut a stress absorbing layer into a predetermined number of absorbing pads and shapes corresponding to the panels of the ball cover.
(8). Attach the absorbing pads of the stress absorbing layer to the panels of the ball cover.
(9). Heat the ball cover and turn the ball cover right side out.
(10). Insert the strengthened bladder into the ball cover through the inlet opening.
(11). Align and glue the valve stem of the bladder with the valve hole of the ball cover.
(12). Semi-inflate the bladder to ensure that the inflated bladder is adapted for propping against the ball cover.
(13). Sew the inlet opening of the ball cover together by hand.
(14). Fully inflate the sportsball to more than a standard pressure within a shaping mold to ensure a permanent structure and shape of the bladder and the ball cover.